Initial import of cf-temp-email deploy CLI

tests/test_subprocess_runner.py

@@ -0,0 +1,19 @@
+from __future__ import annotations
+
+import pytest
+
+from cf_temp_email_deploy.errors import CommandExecutionError
+from cf_temp_email_deploy.subprocess_runner import CommandRunner, CommandSpec
+
+
+def test_command_runner_captures_stdout() -> None:
+    runner = CommandRunner()
+    result = runner.run_checked(CommandSpec(args=("python3", "-c", "print('ok')")))
+    assert result.stdout.strip() == "ok"
+
+
+def test_command_runner_raises_for_non_zero_exit() -> None:
+    runner = CommandRunner()
+    with pytest.raises(CommandExecutionError):
+        runner.run_checked(CommandSpec(args=("python3", "-c", "raise SystemExit(3)")))
+